OBJECTIVE: To introduce the present research situation of treating spinal cord injury using olfactory ensheathing cells (OECs) transplantation from the aspects of biological characteristics, culture, purify of OECs and its application.DATA SOURCES: PubMed database and Chinese Journal Full-text Database were retrieved with key words of "olfactory ensheathing cells, spinal cord injury" from 2000 to 2009. DATA SELECTION: Inclusion criteria: ①The literature was closely associated with OECs and spinal cord injury. ②Literatures about the same circle published in the near future or on the authoritative journals. Exclusion criteria: ①Repetitive study. ②Meta analysis.RESULTS: OECs has similar characteristics to Schwann cells and astrocytes. At present, the research about OECs includes axonal regeneration, cellular replacement, demyelinating prevention and so on. Furthermore, some clinical experiment had been carried on. However, some difficulties exist in clinical trials, such as transplantation dose of OECs, activity of cell factor and transplant risk. We need to do further study on OECs transplantation and more follow up after cells graft. Some research had tried to transplant with gene transfer cells, and satisfactory results were obtained.CONCLUSION: With the development of genetic engineering and research of OECs transplantation, OECs transplantation must bring more hope to patients with spinal cord injury.

BACKGROUND:Astragalus or olfactory ensheathing cell(OECs)transplantation alone can promote survival of various neurons and functional improvement of injured spinal cord.The clinical effect of astragalus in combination with OECs transplantation remains unclear.OBJECTIVE:To observe the effect of astragalus on the proliferation of OECs and the secretion of neurotrophic factors.METHODS:OECs of SD rats,24 hours old,were isolated and cultured,and identified by immunohistochemistry.OECs at culture day 8 were seeded in polylysine-coated 96-well plate and incubated in 5% CO2 at 37℃ for 24 hours,followed by 2 mg/L,20 mg/L,200 mg/L,2 g/L,20 g/L astragalus injection for 24 hours.MTT and flow cytometry were used to assess the effects of astragalus in promoting OECs proliferation;enzyme linked immunoassay(ELISA)was used to measure the content of neurotrophic factors.Serum culture medium was served as negative control.RESULTS AND METHODS:Compared with the negative control group,2 and 20 mg/L astragalus injection significantly promoted OECs proliferation(P＜0.05,P＜0.01).The result of flow cytometry showed that astragalus could promote OECs in G1 stage and reduce the percentage of cells in S and G2 stages,but the difference was not significant(P＞0.05).However,astragatus injection at each mass concentration significantly reduced the number of OECs(P＜0.05).Moreover,2 mg/L astragalus injection significantly promoted in vitro neurotrephic factor levels in OECs.Results show that astragalus injection in combination with OECs can promote recovery of spinal cord injury.

Objective To investigate the effect of Piezo1 activated by mechanical stress on knee osteoarthritis synovial fibrosis via the extracellular signal-regulated kinase(ERK)1/2 signaling pathway.Methods Twenty-five Sprague Dawley rats were divided into blank,exercise,exercise+GsMTx4,exercise+PD98059,and exercise+GsMTx4+PD98059 groups(n=5 per group).After modeling,serum and synovial tissue were extracted and collagen deposition was evaluated by Sirius red and Masson staining.Expression levels of Piezo1,ERK1/2,phospho(p)-ERK1/2,α-smooth muscle actin(SMA),transforming growth factor(TGF)-β,Collagen Ⅰ,and tissue inhibitor of metalloproteinase(TIMP)-1 were detected by Western blot and reverse transcription-quantitative polymerase chain reaction(RT-qPCR),and the interleukin(IL)-1β,IL-6,and tumor necrosis factor(TNF)-α contents were detected by enzyme-linked immunosorbent assay.For cell experiments,synovial cells were divided into blank,pull,pull+GsMTx4,pull+PD98059,and pull+GsMTx4+PD98059 groups and the above indices were detected in the model cells by Western blot,RT-qPCR,and other techniques.Results Mechanical stress increased collagen deposition in synovial tissues in the rats,and increased the protein and mRNA expression levels of the pathway-related and fibrosis-specific indicators Piezo1,p-ERK/ERK,α-SMA,TGF-β,Collagen I,and TIMP-1(P＜0.05).Piezo1 expression was significantly down-regulated by both inhibitors(P＜0.05),but the ERK inhibitor(PD98059)had no significant effect on Piezo1 gene expression.Levels of serum inflammatory factors were significantly higher in the exercise group compared with the blank group(P＜0.05),and levels were significantly reduced by the inhibitors(P＜0.05).The in vitro experiments showed the same trends as the animal experiments.Conclusions The Piezo1 ion channel can sense mechanical stress and activate the ERK 1/2 pathway to mediate knee synovial fibrosis.